Toulon is a city in Stark County, Illinois, United States. The population was 1,292 at the 2010 census. It is the county seat of Stark County. Toulon is part of the Peoria, Illinois Metropolitan Statistical Area, and is the northwestern terminus of the Rock Island Trail State Park.

Stark County is in Illinois. According to the 2020 census, it had a population of 5,400. Its county seat is Toulon.